Device for assisting the positioning of medical devices

ABSTRACT

In one embodiment, a needle guide is attached to the end of an ultrasonic probe in a manner such that the needle will follow a known trajectory under control of the needle guide. The surgeon then positions the needle guide by looking at the ultrasound image formed from the ultrasound radiated from the probe. In one embodiment, the needle guide has a release mechanism that allows the needle (or other medical device) that had been positioned in the guide to remain in the patient when the probe is removed. In one embodiment, the needle guide is designed to be releasably mounted to a bracket which, in turn, is releasably mounted to the end of the probe.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of, and claims priority to U.S. patent application Ser. No. 10/766,707 filed Jan. 28, 2004, entitled SYSTEMS AND METHODS FOR ASSISTING IN POSITIONING OF MEDICAL DEVICES. Which claims priority to U.S. Provisional Patent Application No. 60/528,505 filed Dec. 10, 2003, entitled DEVICE FOR ASSISTING THE POSITIONING OF MEDICAL DEVICES, and, the disclosures of which are hereby incorporated by reference in their entirety.

TECHNICAL FIELD

This invention relates to medical positioning devices and more particularly to systems and methods for using imaging equipment, such as ultrasound, for assisting in the placement of a medical device.

BACKGROUND

Proper positioning of medical devices, such as needles, catheters, drills, saws and even scalpels, is critical in the proper performance of certain medical procedures. Often the surgeon must look at a screen while trying to manually position a medical device, and thus can not look directly at the device. This is difficult at best and sometimes results in improper angles of attack and could result in improper placement of the medical device.

SUMMARY

In one embodiment, a needle guide is attached to the end of an ultrasonic probe in a manner such that the needle will follow a known trajectory under control of the needle guide. The surgeon then positions the needle guide by looking at the ultrasound image formed from the ultrasound radiated from the probe.

In one embodiment, the needle guide has a release mechanism that allows the needle (or other medical device) that had been positioned in the guide to remain in the patient when the probe is removed.

The foregoing has outlined rather broadly the features and technical advantages of the present invention in order that the detailed description of the invention that follows may be better understood. Additional features and advantages of the invention will be described hereinafter which form the subject of the claims of the invention. It should be appreciated that the conception and specific embodiment disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present invention. It should also be realized that such equivalent constructions do not depart from the invention as set forth in the appended claims. The novel features which are believed to be characteristic of the invention, both as to its organization and method of operation, together with further objects and advantages will be better understood from the following description when considered in connection with the accompanying figures. It is to be expressly understood, however, that each of the figures is provided for the purpose of illustration and description only and is not intended as a definition of the limits of the present invention.

DESCRIPTION OF THE DRAWINGS

FIG. 1 shows one embodiment of a probe having a medical device positioning guide mounted thereon;

FIG. 2 shows a view of the positioning guide of FIG. 1;

FIG. 3 shows one embodiment of a medical device guide and release mechanism based on the embodiment of FIG. 1;

FIG. 4 shows one embodiment of a needle held by the medical device guide;

FIG. 5 shows details of one embodiment of the release mechanism based on the embodiment of FIG. 1;

FIG. 6 illustrates how the release mechanism of FIG. 5 releasably mates with the device guide of FIG. 1;

FIGS. 7A, 7B and 7C illustrate the releaseable mating of the device bracket with the probe;

FIGS. 8A, 8B and 8C illustrate the releaseable mating of the device guide with the device bracket;

FIGS. 9A, 9B, 9C and 9D show dimensional relationships of embodiments of the illustrated device guide;

FIGS. 10A, 10B and 10C show dimensional relationships of embodiment of the illustrated release mechanism; and

FIG. 11 shows one embodiment of packaging a plurality of device guides; and

FIGS. 12 and 13 show alternate embodiments of the medical device guides.

DETAILED DESCRIPTION

FIG. 1 shows one embodiment of probe 10 having bracket 12 releasably attached thereto. This attachment, for example, is by fitting a first side 71 of the bracket over protrusion 13 on probe 10, as shown in FIG. 7A. The other side 72 of the bracket fits over the other side 15 of probe 10 as shown in FIG. 7B, and locks between protrusions 73 and 74 up against slot 14 of probe 10 again, as shown in FIG. 7C. Slot 702 snaps over protrusion 13 to hold bracket 12 from swinging open. Probe 10, in the embodiment of FIG. 1, can be an ultrasound probe.

In operation, probe 10 (FIG. 1) sends ultrasound signals into the body and these signals then provide images of organs, fluids, etc which are otherwise hidden from view. When the probe is positioned properly, as determined by the images sent back by the ultrasound, the surgeon can then insert a needle, such as needle 41, (or other surgical instrument), knowing the instrument's trajectory based upon the received images. The trajectory is a preset by the selection of the device guide. The device guide establishes an angle of attack with respect to the proximal end of the probe. By extension, this angle of attack extends below the skin of the patient. In some cases, the image may contain a projection of the needle trajectory as an aide to the surgeon.

When the needle, or other device to be inserted, is positioned properly, the needle is slid forward so that its proximal end moves toward the patient and enters the patient. When the desired depth is reached, mechanism 50 is operated to release the needle thereby allowing probe 10, bracket 12 and needle guide 20 to be removed, leaving the needle (or other device) within the patient's body.

FIG. 2 shows bracket 12 having medical device guide 20 mounted thereon. Note that device 20 and device 12 can be a single structure if desired. Device 20 in the embodiment shown, is a device for holding a needle (shown in FIG. 4) within groove 22. Release control portion 50 holds the needle in position, while end portion 51 serves to release the needle when the needle has been properly positioned. If device 20 and device 12 are separate structures, they can be releasably mated as shown in FIGS. 8A and 8B. As shown in FIG. 8A, one end of device 20 is mated via pins 82 (shown in FIG. 8C) being inserted into bracket 82. Once pin 83 is positioned in bracket 82, guide 20 is rotated toward probe 10 and snaps in position under control of tab 81 of bracket 12 releaseably locking on edge 21 of device 20.

As shown in FIG. 3, device guide 30 consists of two parts: namely, guide 20 and release mechanism 50. Guide 30 snaps into bracket 12, as discussed above, attached to an ultrasound transducer. The device guide is manufactured to control the placement of devices, such as catheter and needles, to multiple depths, by changing the angle of attack at which the needle (or catheter) is presented to the transducer. The device guide is also manufactured to handle multiple gauges to accommodate specific diameter medical devices.

As shown in FIG. 4, guide 20 has lead-in 43 to make insertion of the needle (such as needle 41) into the guide easier. Needle 41 then rests in channel 44 along the longitudinal axis of probe 10 so that the needle is positioned in a specific trajectory with respect to the surface to be probed. In effect, the medical device (which typically would be an elogated device (needle) with a substantially round cross-section forms a closing angle with the proximal end of the guide (and the probe) so that when the probe is properly placed, the proximal end, when moved down the channel, will be positioned a given distance below the skin of the patient. This trajectory intersects the patient at the target depth (such as 1.5 cm.) as indicated on the needle guide. Various angles and respective depths for 1.5, 2.5, 3.5 and 4.5 cms are shown in FIG. 9A-9D.

FIG. 4 shows mechanism 50 (discussed in more detail with respect to FIGS. 6 and 7) mounted in slot 45 of guide 20. Release portion 52 is positioned over needle 41 and exerts pressure on needle 41 within groove 44. The pressure from portion 52 on the needle guide keeps the needle in proper orientation, but allows the user to slide the clamped needle toward the patient. The needle can then be positioned below the skin of the patient at the desired depth.

FIG. 5 shows mechanism 50 having flexible tab 55 to maintain a closed position and to prevent accidental opening. The geometry of mechanism 50, including dimension D, provides a specific amount of needle drag friction between the inserted needle and groove 44. Once the needle has been oriented into the desired position, tab 55 is flexed inward allowing mechanism 50 (and particularly overhang 52) to move away from groove 44, thereby allowing needle 41 to release from the device guide. This, then, allows needle 41 to remain in the patient when the probe is removed.

FIG. 6 shows a top schematic view of mechanism 50 inserted in guide 20 with tab 55 locking against edge 42 of guide 20 prior to release of mechanism 50 from guide 20. Tab 55 flexes into slot 53 formed by opening 54.

FIGS. 9A-9D show dimensional relationships of embodiments of a device guide. FIG. 9A shows a top view of guide 20. FIG. 9B is an end view of guide 20 and FIG. 9C is a section 9C-9C taken through device 20 in FIG. 9B. FIG. 9D shows typical illustrative dimensions (keyed to FIG. 9C) for different depth guides.

FIG. 10A shows a top view of mechanism 50. FIG. 10B shows the end view of mechanism 50 and FIG. 10C is a section 10C-10C taken through mechanism 50 in FIG. 10B. Dimension D is keyed to the diameter of the device to be held within the guide. For 18 gauge needles, this dimension would be 0.070 in for the embodiment shown, and dimension D1 would be 0.096 in. A typical length for mechanism 50 would be 0.564 in. If desired, portion 501 (FIG. 10C) can be tapered to better wedge needle 41 when in seating portion 44 of the guide.

FIG. 11 shows one embodiment 1100 of the packaging for a plurality of needle guides, 50, 1110, 1111 and 1112. Each of the needle guides can have different target depths, or they can all have the same depth. Center holder 1101 has limbs 1102 for holding each guide. Any number of limbs can be used.

FIG. 12 shows one alternate device guide 1200 with latch 1201 in the open position. As shown, latch 1202 will engage protrusion 1203 for latching purposes.

FIG. 13 shows guide 1200 in the latched position clamping needle 41 in position.

Although the present invention and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the invention as defined by the appended claims. Moreover, the scope of the present application is not intended to be limited to the particular embodiments of the process, machine, manufacture, composition of matter, means, methods and steps described in the specification. As one will readily appreciate from the disclosure, processes, machines, manufacture, compositions of matter, means, methods, or steps, presently existing or later to be developed that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein may be utilized. Accordingly, the appended claims are intended to include within their scope such processes, machines, manufacture, compositions of matter, means, methods, or steps. 

1. An apparatus for positioning a medical device for insertion within a body; said apparatus comprising: a bracket configured to attach to the body of an imaging probe; and a plurality of medical device supports, said plurality of medical device supports being configured to individually attach to said bracket, one or more of said plurality of medical device supports configured to create a different angle of attack than another of said plurality of medical device supports, said plurality of device supports including a latch configured to hold a medical device at a predetermined angle with respect to said probe such that images produced as a result of radiation from said probe serve to position said medical device for insertion within said body.
 2. The apparatus of claim 1 wherein said bracket comprises: slots for fitting over the proximal end of said image probe without interference with said radiation from said probe.
 3. The apparatus of claim 2 wherein said latch comprises: at least one tab for maintaining said medical device at said predetermined angle.
 4. The apparatus of claim 1 wherein the first medical device support of said plurality of medical device supports is configured to be pivotably coupled to said bracket.
 5. The apparatus of claim 1 further comprising: means for controlling the release of said medical device after positioning within said body.
 6. The apparatus of claim 5 wherein said controlling means comprises: a latch for sliding over a surface of said medical device.
 7. The apparatus of claim 5 wherein said controlling means comprises: a latch for pivoting over a surface of said medical device.
 8. The apparatus of claim 1 wherein said medical device is selected from the list of: a needle, a catheter, a drill bit, a cutting blade.
 9. The apparatus of claim 1 wherein said latch is a slide configured to traverse perpendicularly over said medical device when said medical device is seated in one of said plurality of medical device supports.
 10. A method of releasably attaching a medical device to a probe, said method comprising: releasably connecting a bracket to the proximal end of said probe; releasably connecting a guide to said bracket, so that the longitudinal axis of said guide falls along the longitudinal axis of said probe, said guide being selected from a plurality of guides which are adapted to form different angles of attack for said medical device; positioning said medical device along said longitudinal axis of said guide; and releasably clamping said positioned medical device within said guide so that an angle of attack of the selected medical device remains constant with respect to the proximal end of said probe.
 11. The method of claim 10 further comprising: generating at least one image of structures below the surface of an object over which said proximal end of said probe moves, said image generation resulting at least in part from signals emitted from said proximate end of said probe; sliding a proximal end of said clamped medical device toward said surface of said object along a trajectory predictable as a result of said generated image; continuing to slide said proximal end of said clamped medical device along said trajectory to a position below said surface of said object; and releasing said clamped positioned medical device from said probe while said proximal end of said medical device remains positioned below said surface of said object.
 12. The method of claim 11 wherein said guide is configured to define a closing angle with respect to said proximal end of said probe and wherein said trajectory is predictable at least in part by said closing angle.
 13. The method of claim 12 wherein said closing angle corresponds to a target depth of said positioned medical device below said surface of said object.
 14. The method of claim 10 wherein said releasably clamping is controlled at least in part by a slide operating transverse perpendicular to said longitudinal axis.
 15. The method of claim 14 wherein at least a portion of said slide contains a ramp.
 16. The method of claim 10 wherein said plurality of guides are configured to accept medical devices having different diameters.
 17. A device comprising: a releasable guide configured to mate with said proximate end of an imaging probe; a channel configured to accept the longitudinal axis of an elongated medical device, said channel lying along a longitudinal axis of said probe when said guide is mated with said probe, said channel defining a pre-established closing angle with respect to a location below a surface of an object in proximity to said proximate end of said probe; and a slide configured to traverse perpendicularly over said channel, said slide applying controlled clamping force on an accepted elongated medical device.
 18. The device of claim 17 wherein said slide further comprises: at least one tab configured to maintain said applied controlled clamping force.
 19. The device of claim 18 wherein said controlled clamping force allows the proximal end of said clamped elongated medical device to slide toward said surface of said object under control of a user.
 20. The device of claim 17 wherein said releasable guide comprises: a bracket releasably affixed to both said guide and said proximate end of said probe.
 21. A device for securing a medical implement at a pre-determined angle, said device comprising: a guide defining said pre-determined angle, said guide further defining a longitudinal channel configured to accept said medical implement; a latching mechanism configured to secure said medical implement in longitudinal channel of said guide, said latching mechanism including a flexible portion configured compress in order to insert said latching mechanism into said guide and further configured to expand and provide a secure latch when inserted into said guide and when said latching mechanism is in a closed position.
 22. The device of claim 21 wherein said latching mechanism comprises a lower portion configured to be placed below said channel and an upper portion configured to be placed above said medical implement.
 23. The device of claim 22 wherein said lower portion comprises a sloped surface keyed to a diameter of said medical implement.
 24. The device of claim 21 wherein said flexible portion comprises a tab.
 25. The device of claim 21 wherein said flexible portion is configured to be depressed when said latching mechanism is in a closed position in order to release said latching mechanism.
 26. The device of claim 21 wherein said latching mechanism is slidably coupled to said guide.
 27. The device of claim 26 wherein said latching mechanism is configured to slide perpendicularly across said longitudinal channel to secure said medical implement. 